Irish authorities are liaising with Polish officials over the source of the contamination.
Traces were found at Rangeland Foods in Co Monaghan, owned by ABP Food Group.
The Group has lost contracts with:
- Co-Operative Group
- Burger King
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Michael Fallon has received reassurances from his US counterpart that security ties with Britain will "endure" following a vote for Brexit.
On Friday, police said it appeared the girl had shot herself in the face with the weapon.
The showers will be slow-moving, heavy and thundery at times, particularly in central and eastern areas.